To resolve the B173D fault without spending unnecessary money at the dealership, follow this structured diagnostic pathway. Step 1: Perform a Key Fob Battery and Hardware Check
(car won't turn on, despite the key being inside).
(Engine ECU Immobilizer Reading Error) B173A (Driver's Door Presence Detection Error) Scan Tools Required b173d peugeot
An invalid identifier fault can originate from the key itself, the reader component, or the wiring infrastructure linking the security units together. 1. Depleted Key Fob Battery
Key Present inside the Reader: (Should toggle between Yes/No) Key Label Recognised: (Should display Valid or Confirmed) Immobiliser Status: (Locked vs Unlocked) To resolve the B173D fault without spending unnecessary
: If a remote control button is pressed repeatedly out of range of the vehicle, its rolling code counter can lose alignment with the BSI memory.
Disclaimer: This information is for educational purposes based on common Peugeot diagnostic patterns. Always consult a certified mechanic. Always consult a certified mechanic
If the battery and fuses are fine and the code is intermittent, the BSI reset is often the definitive solution. This procedure essentially performs a "hard reboot" of the system.
Before spending hundreds at a dealership, try these steps in order: 1. Replace the Key Fob Battery
Try to start the car without other electronic devices in close proximity to the steering column. 3. Faulty Hands-Free Antennas